Is Continuity from Running Lights or Brakes to Ground Normal When Installing a Junction Box

Question:

Good day. I am in the process of adding a 7 wire junction box to my trailer. The trailer currently has 4 wire flat harness. White ground green right yellow left and brown running lights. Also equipped with electric brakes. All is proceedings well until I decide to test continuity from the 7 pin plug to the junction box. My questions on continuity checks are 1. I am getting continuity from running lights to ground is this normal? 2. I am getting continuity on the electric brakes positive and ground wire. Also is this normal?

asked by: Lee

Expert Reply:

Yes, the continuity you are seeing after connecting your wiring to your junction box, like part # 277-000141, is normal. The only way that you wouldn't get continuity is if there was a break in the circuit somewhere.

If you have your tow vehicle handy you can also test your wiring by simply connecting the 7-Way from your junction box to the 7-Way on your vehicle. You can then run through each light function to make sure your lights are working properly and use the manual override on your brake controller to make sure your controller is sending power to the brakes. The reason you use the manual override instead of just pressing the brake pedal is because some controllers, like the Prodigy P3 # 90195, use proportional braking and so if your vehicle is sitting still it won't send enough power back to activate your brakes.

expert reply by: Jon G